Substituted Cellulose Acetates and Uses Thereof

ABSTRACT

The present invention relates to substituted cellulose acetates and methods of use thereof. One embodiment of the present invention provides a coating having a substituted cellulose acetate having a polar substituent that has an oxygen atom covalently bonded to a nonmetal selected from the group of sulfur, phosphorus, and boron; wherein the nonmetal is present in at least about 0.01% by weight of the substituted cellulose acetate.

BACKGROUND

The present invention relates to synthetic polymers and, in particular,to substituted cellulose acetates, and methods of use thereof.

Cellulose acetate is an acetate ester derivative of cellulose, anaturally occurring biopolymer comprising β-D-glucose monomer units, andis widely used to make a variety of consumer products. Naturallyoccurring cellulose is insoluble in water and most organic solvents.However, the three free hydroxyl groups of each glucose monomer unit incellulose can be derivatized to modify certain properties, for example,solubility in certain solvents. Cellulose acetate is thought to be amongthe most commercially useful derivatives of cellulose, and its specificphysical and chemical properties generally depend largely on the degreeof substitution of acetate on the three free hydroxyl groups of aglucose monomer unit.

Since its first synthesis, cellulose acetate has been used, among otherthings, as a film base in photography, a component in adhesives, and araw material used in the manufacture of cigarette filters. One of thekey attributes of cellulose acetate is that it can be processed intomany different shapes and forms, including, films, tows, flakes, fibers,and solids, depending on the desirability of the application. Forexample, cellulose acetate tow is primarily used in the manufacture ofcigarette filters.

Most typically, derivatization of cellulose is conducted using acidiccatalysts at elevated reaction temperatures. The synthesis of celluloseacetate involves acetylating cellulose, which is commonly obtained fromwood pulp, in the presence of acetic anhydride and acids. Acetic acidand sulfuric acid are the two acids usually present during theacetylation reaction. In this reaction, the acetic anhydride serves asthe primary acetylating agent; the acetic acid is used primarily as adiluent; and a small amount of the sulfuric acid is used as thecatalyst. In general, the monomeric units of cellulose have threehydroxyl groups that are readily available for substitution, e.g., viaacetylation. The monomeric units at both ends also have an additionalhydroxyl group that are typically involved inter-sugar linkages.

The product of the acetylation reaction is a primary cellulose acetatethat usually contains high concentration levels of acetate or, in otherwords, has a high degree of substitution (DS) of acetate. As usedherein, “degree of substitution of acetate” generally refers to theaverage number of acetates per glucose monomer unit. The structure ofcellulose acetate may be generally characterized by specifying thedegree of substitution of acetate. Exhaustively acetylated cellulose iscommonly referred to as cellulose triacetate, where, according toFederal Trade Commission guidelines, at least 92% of the hydroxyl groupsare substituted with acetyl groups. For example, when there are at leastabout two acetyl groups per cellulose monomer unit (that is, a DS ofabout 2), the acetyl cellulose can become significantly lessbiodegradable until at least some of the acetyl groups are removed viachemical or enzymatic hydrolysis. Acetylated cellulose having reduced DSof acetate can be prepared by controlled hydrolysis of cellulosetriacetate.

Next, the primary cellulose acetate is hydrolyzed in the presence ofacetic acid and sulfuric acid to reduce the DS of acetate of the primarycellulose acetate. The resulting hydrolysis product is usually acellulose acetate flake having a DS on the order of about 2.4 to about2.6.

Once cellulose acetate flake is obtained, it may be subjected to furthertreatment in order to process the cellulose acetate to its desired form.For example, cellulose acetate tow may be formed by dissolving thecellulose acetate flakes in acetone, putting cellulose acetate solutionthrough a series of filtration processes, and dry spinning the acetonedope through microscopic holes in a spinneret. As the cellulose acetatemoves through this extrusion process, filaments of cellulose acetate arecollected. These filaments are typically bundled and then crimped toensure tow band cohesion as well as desired bulk. The end result is acellulose acetate tow, which is essentially a continuous band composedof several thousand filaments held loosely together by crimp. Thecellulose acetate tow filaments usually are very thin and may be packedtogether tightly to create a filter. As used herein, “cellulose acetatetow” generally refers to post-synthesis processed bundles of filamentsof cellulose acetate.

Cellulose acetate is also environmentally friendly in that it is areadily degradable material made largely from a renewable source, woodpulp. While cellulose acetates that vary in their DS of acetate arestructurally similar, this variation can have some effect on thebiodegradability of the cellulose acetate. At higher degrees of acetylsubstitution, the rate of biodegradation can be significantly reducedrelative to naturally occurring cellulose or cellulose having lessacetyl substitution. Cellulose acetates having a lower DS of acetatebiodegrade more readily than cellulose acetates having a higher DS ofacetate. This trend is believed to taper off at lower DS of acetatevalues because the material becomes insoluble in water. In one example,the biodegradation rates of cellulose acetate having DS values of 1.85,2.07, and 2.57 were tested for their biodegradability (FIG. 1). Thecellulose acetate with a DS of 1.85 showed the highest biodegradationrate while the cellulose acetate with an acetyl value of 2.57 showed theslowest biodegradation rate.

While cellulose acetate is a versatile composition with many commercialuses, the properties of certain cellulose acetate derivatives have notbeen exhaustively studied. For example, in a typical synthesis, residualsulfate groups are typically removed in order to improve thermalstability. As a result, cellulose acetates synthesized by typical meanswill have about 0.005% or less of sulfur atoms by weight. As such, thereare potential derivatives of cellulose acetate that may provide enhancedproperties for many of the consumer applications of cellulose acetate.

SUMMARY OF THE INVENTION

The present invention relates to synthetic polymers and, in particular,to substituted cellulose acetates, and methods of use thereof.

In some embodiments, the present invention provides diapers comprising:an inner layer comprising an absorbent core comprising a substitutedcellulose acetate comprising a polar substituent that comprises anoxygen atom covalently bonded to a nonmetal selected from the groupconsisting of: sulfur, phosphorus, boron, and chlorine; wherein thenonmetal is present in at least about 0.01% by weight of the substitutedcellulose acetate; and an outer layer.

In other embodiments, the present invention provides bandagescomprising: an absorbent layer comprising a substituted celluloseacetate comprising a polar substituent that comprises an oxygen atomcovalently bonded to a nonmetal selected from the group consisting of:sulfur, phosphorus, boron, and chlorine; wherein the nonmetal is presentin at least about 0.01% by weight of the substituted cellulose acetate;and a strip designed to place the absorbent layer in contact with awound.

In still other embodiments, the present invention provides potting soilcompositions comprising: an organic compost; and an absorbentcomposition comprising a substituted cellulose acetate comprising apolar substituent that comprises an oxygen atom covalently bonded to anonmetal selected from the group consisting of: sulfur, phosphorus,boron, and chlorine; wherein the nonmetal is present in at least about0.01% by weight of the substituted cellulose acetate.

In still other embodiments, the present invention provides amended soilcompositions comprising: a soil composition; and a water retentionadditive comprising a substituted cellulose acetate comprising a polarsubstituent that comprises an oxygen atom covalently bonded to anonmetal selected from the group consisting of: sulfur, phosphorus,boron, and chlorine; wherein the nonmetal is present in at least about0.01% by weight of the substituted cellulose acetate.

In still other embodiments, the present invention provides articlescomprising: a nonwoven layer that comprises fibers from a substitutedcellulose acetate comprising a polar substituent that comprises anoxygen atom covalently bonded to a nonmetal selected from the groupconsisting of: sulfur, phosphorus, boron, and chlorine; wherein thenonmetal is present in at least about 0.01% by weight of the substitutedcellulose acetate.

In still other embodiments, the present invention provides methodscomprising: providing a substituted cellulose acetate comprising a polarsubstituent that comprises an oxygen atom covalently bonded to anonmetal selected from the group consisting of: sulfur, phosphorus,boron, and chlorine; wherein the nonmetal is present in at least about0.01% by weight of the substituted cellulose acetate; and placing thesubstituted cellulose acetate in an absorbent article.

In still other embodiments, the present invention provides methodscomprising: providing an absorbent material comprising a substitutedcellulose acetate comprising a polar substituent that comprises anoxygen atom covalently bonded to a nonmetal selected from the groupconsisting of: sulfur, phosphorus, boron, and chlorine; wherein thenonmetal is present in at least about 0.01% by weight of the substitutedcellulose acetate; and placing the absorbent material in a diaper.

The features and advantages of the present invention will be readilyapparent to those skilled in the art upon a reading of the descriptionof the preferred embodiments that follows.

BRIEF DESCRIPTION OF THE DRAWING

The following figures are included to illustrate certain aspects of thepresent invention, and should not be viewed as exclusive embodiments.The subject matter disclosed is capable of considerable modification,alteration, and equivalents in form and function, as will occur to thoseskilled in the art and having the benefit of this disclosure.

FIG. 1 shows a biodegradability plot of cellulose acetate with varyingdegrees of substitution.

FIG. 2 shows water absorbency data as described in Example 3.

FIG. 3 shows water absorbency data as described in Example 3.

FIG. 4 shows water absorbency data as described in Example 3.

FIG. 5 shows water absorbency data as described in Example 3.

DETAILED DESCRIPTION

The present invention relates to synthetic polymers and, in particular,to substituted cellulose acetates, and methods of use thereof.

The present invention provides compositions, methods, and processesrelated to substituted cellulose acetates that have a number ofadvantageous and/or desirable properties. The substituted celluloseacetates of the present invention may be utilized in a variety ofapplications including a number of consumer products, especially whereabsorbency, adhesiveness, and/or degradability, may be useful.

As used herein, the term “substituted cellulose acetate” generallyrefers to a cellulose acetate that has at least one polar substituentsubstituted on the hydroxyl group of a cellulose polymer. As usedherein, a “polar substituent” is a non-acetyl chemical moiety comprisingan electronegative atom (e.g., oxygen) bonded to a nonmetal (e.g.,sulfur, phosphorus, boron, and chlorine) atom.

It has been surprisingly discovered according to the present inventionthat substituted cellulose acetate composition having relatively highweight percentage of at least one nonmetal atom corresponding to a polarsubstituent having a relatively high degree of substitution can beprovided. Moreover, it has also been surprisingly discovered, that thepercentage weight of nonmetal atoms, may be adjusted and/or modified toyield or enhance various properties of substituted cellulose acetate asdescribed herein.

The substituted cellulose acetates of the present invention are, in someembodiments, versatile (i.e., possess many distinct desirable chemicaland physical properties) and environmentally friendly (i.e., made fromrenewable sources, degradable, biodegradable, etc.) materials suitablefor use in a number of consumer products.

As used herein, “degradable” refers to the ability of a material todecompose and/or break down into simpler parts. As used herein,“biodegradable” refers to the ability of a material to degrade by theaction of living things. Depending on the application, the definition of“biodegradable” may be subject to the results of standard tests, forexample, the Organisation for Economic Co-operation and Development(OECD) testing protocols.

Without being limited by theory, it is believed that by adjusting thepercentage weight of the nonmetal atom of a polar substituent, asubstituted cellulose acetate of the present invention can provide newor enhanced chemical and/or physical properties. For example, it isbelieved that certain polar substituents (e.g., sulfate) can increasethe hydrophilicity of the substituted cellulose acetate as well asincrease the potential for electrostatic interaction.

The substituted cellulose acetate compositions, which are described inmore detail hereinafter, have certain advantageous properties andcommercial roles (e.g., as an adhesive, chemical stabilizer, absorbent)that may be imparted or enhanced based on the percentage weight ofnonmetal atom present. In some embodiments, tuning the percentage weightof the nonmetal atom may remove or reduce an undesirable quality orproperty in the substituted cellulose acetate.

A substituted cellulose acetate may be described by the concentration ofits polar substituents which, in turn, may be specified in terms ofdegree of substitution of the polar substituent (i.e., average number ofsubstituent per glucose monomer unit) or as a percentage weight of thenonmetal (e.g., sulfur, phosphorus, boron, and chlorine) atom presentrelative to the total weight of the substituted cellulose acetate. Inpractical terms, modifying the degree of substitution of a polarsubstituent will also modify the percentage weight of the nonmetal atomon a substituted cellulose acetate by a predictable amount and viceversa. Accordingly, it may be assumed that increasing the degree ofsubstitution of a polar substituent will generally increase thepercentage weight of the nonmetal atom present on a substitutedcellulose acetate. Conversely, decreasing the degree of substitution ofa polar substituent will generally decrease the percentage weight of thenonmetal atom present in a substituted cellulose acetate by apredictable amount.

In theory, the percentage weight of the nonmetal atom in a substitutedcellulose acetate may range from about 0.01% to about 25%, whichcorresponds to a cellulose acetate that has few polar substituents (insome cases, significantly and surprisingly more than typically preparedcellulose acetate) and a cellulose acetate that has been exhaustivelysubstituted. While the present invention is preferably practiced byspecifying the percentage weight of the nonmetal of the polarsubstituent, the present invention may be equivalently practiced byspecifying the degree of substitution of the polar substituent or othersimilar measures of concentration. The degree of substitution of a polarsubstituent may range from about 0.005 to about 3.

Various embodiments described herein utilize substituted celluloseacetate having a polar substituent in a wide range of consumer products.By adjusting the percentage weight of the nonmetal atom of the polarsubstituent, it is believed that the substituted cellulose acetatecompositions of the present invention may be used, among many things, asan effective absorbent, an adhesive, a chemical stabilizer, and astabilizing film forming agent. For example, by adjusting the percentageweight of a sulfur atom (e.g., of a sulfate substituent), thesubstituted cellulose acetate of the present invention may go from awater-soluble material to a water-swellable material. In someembodiments, the water-swellable substituted cellulose acetatecomposition may be used as a degradable coating to encapsulate, forexample, a pharmaceutical composition so that the release of thepharmaceutical composition is delayed in the body. Other properties thatmay be adjusted include, but are not limited to, solubility in certainsolvents, ability to stabilize emulsions, adhesiveness to varioussurfaces, and biodegradability. These properties may be further adjustedby modifying the percentage weight of the nonmetal atom of the polarsubstituent present in the substituted cellulose acetate as needed. Aperson of ordinary skill in the art should be able to modify thepercentage weight of nonmetal as necessary in order to practice the manyembodiments of the present invention.

In some embodiments, modifying the degree of substitution of acetate mayalso yield or enhance certain properties of the substituted celluloseacetate. In some embodiments, the water-soluble substituted celluloseacetate has a degree of substitution of acetate between about 0.4 toabout 1. In some embodiments, the water-swellable substituted celluloseacetate has a degree of substitution of acetate between about 1 to about2. As the degree of substitution of acetate is varied between 0.05 to 3,the appropriate solvent system may change.

In some embodiments, at the relatively lower degree of substitution ofacetate, water is an appropriate solvent. In some embodiments, at therelatively higher degree of substitution of acetate, an organic solventis required. The degree of substitution may be varied so that a solventsystem can be selected that is appropriate to the targeted end use.

In some embodiments, the degree of substitution of a polar substituentmay be kept relatively fixed while the degree of substitution of acetateis adjusted. In some embodiments, the combination of adjusting thedegree of substitution of polar substituent and degree of substitutionof acetate provides the substituted cellulose acetate with the desiredproperties. In some embodiments, the range of degree of substitution ofpolar substituent may affect the range of degree of substitution ofacetate that is needed to provide the substituted cellulose acetate withthe desired properties. In some embodiments, the range of degree ofsubstitution of acetate may affect the range of degree of substitutionof polar substituent that is needed to provide the substituted celluloseacetate with the desired properties.

The potential commercial uses of substituted cellulose acetate of thepresent invention are wide ranging and include, but are not limited to,household articles such as buttons, glasses, linings, blouses, dresses,wedding and party attire, home furnishings, draperies, upholstery, slipcovers, and the like. Other commercial uses include filters includingcigarette, ink reservoirs, playing cards, and the like, and highabsorbency products such as diapers and surgical products.

In some embodiments, as an absorbent, the substituted cellulose acetatesof the present invention have a water absorption capacity several times(for example, from about 8 times to about 24 times) its weight in anaqueous-based fluid (e.g., water, saline solution, etc.) depending onthe percentage weight of the nonmetal atom present on the substitutedcellulose acetate.

In some embodiments, the substituted cellulose acetates of the presentinvention may be effective as an adhesive, able to glue a variety ofsubstrates including, but not limited to, cardboard, plastic, paper,glass, wood, hemp, saw dust, composites (e.g., fiber reinforcedcomposites), wood shavings and the like. It is also believed that thesubstituted cellulose acetates of the present invention may be aneffective chemical/colloidal stabilizer, able to stabilize variousemulsion mixtures.

In some embodiments, the substituted cellulose acetates of the presentinvention may be used as a stabilizing film forming agent to promote theformation of film of a given mixture. In some embodiments, the formedfilm may be clear.

The substituted cellulose acetate may exist in many different forms andbe utilized in many different ways. In some embodiments, the substitutedcellulose acetate may be fibers, woven fabrics, nonwoven fabrics, towsor tow bands (open or non-open), flakes, foams, emulsions, films, gels,dispersions, solutions, pastes, suspensions, and combinations thereof.In some embodiments, the substituted cellulose acetate may be used ascoatings, additives, films, layers, cores, and the like.

In some embodiments, the present invention also provides processes forforming substituted cellulose acetate into various shapes of substitutedcellulose acetate (e.g., substituted cellulose acetate tow). Theseprocesses typically put the substituted cellulose acetate in a betterform to be utilized in certain applications. For example, fibers ofsubstituted cellulose acetate may have the particularly desirableproperties of being able to selectively absorb and remove levels ofcertain organic chemicals; being water-soluble or water-swellable;having a high surface area; and being compatible with dyes. It is alsobelieved that the fibers of substituted cellulose acetate may haveresistance to mold and mildew. A substituted cellulose acetate may beparticularly desirable in textile applications.

While at least some embodiments relate to cellulose acetates having atleast one polar substituent, derivatives of cellulose acetates having atleast one polar substituent may also be used in accordance with any ofthe compatible embodiments of the present invention. Derivatives ofcellulose acetate may include, but are not limited to, cellulose acetateesters, cellulose acetate mixed esters, and the like. Suitable examplesof cellulose acetate esters include, but are not limited to, celluloseacetate propionates, cellulose acetate butyrates, and the like. Thedegree of esterification of the cellulose acetate esters will depend, atleast in part, on the particular application and will be apparent tothose of ordinary skill in the art.

The substituted cellulose acetate of the present invention may becharacterized by having a polar substituent that comprises an oxygenatom covalently bonded to a nonmetal selected from the group consistingof: sulfur, phosphorus, and boron; wherein the nonmetal is present in atleast 0.01% by weight of the substituted cellulose acetate. In someembodiments, the nonmetal may be present in no more than about 25% byweight of the substituted cellulose acetate. Without being limited bytheory, it is believed the upper limit of 25% by weight corresponds to afully substituted cellulose derivative (e.g., sulfate). The exact rangeof nonmetal weight percentage will depend on, among other things, thechemical makeup of the polar substituent.

Generally, at least a portion of hydroxyl groups on a substitutedcellulose acetate will be substituted by acetate. In some embodiments,the degree of substitution of acetate will be from about 0.05 to about3, preferably from about 0.4 to about 2. In some embodiments, the ratioof degree of substitution of acetate to degree of substitution of polarsubstituent may be adjusted to produce or enhance the desired propertyof a substituted cellulose acetate of the present invention. In someembodiments, the DS of acetate is higher than the DS of the polarsubstituent.

Optionally, the substituted cellulose acetate may further comprise or bemixed with a plasticizer. Suitable examples of plasticizers include, butare not limited to, glycerin, glycerin esters (including mono, di ortriacetyl glycerin and glycerin esters), polyethylene glycol, diethyleneglycol, propylene glycol, dimethyl sulfoxide, glycerol triacetate,triethylene glycol diacetate, derivatives thereof, combinations thereof,and mixtures thereof. In some embodiments, the plasticizer comprises aplasticizer selected from the group consisting of esters of saturateddibasic acids, esters of saturated polyhydric alcohols, fatty acidesters, sulfonamide resins, derivatives thereof, and combinationsthereof. Plasticizers may be added to the substituted cellulose acetatein order to lower the glass transition temperature (T_(g)) and themelting point of the composition. Plasticizers typically function tofacilitate processing and to increase the flexibility and toughness ofthe final product. It is also believed that certain plasticizers (e.g.,ether ester, simple ester type, etc.) may increase the capacity ofsubstituted cellulose acetate filters for phenol removal which is auseful property in cigarette filters.

In some embodiments, the polar substituent may be selected from thegroup consisting of sulfates, phosphates, borates, carbonates, andcombinations thereof. In some embodiments, the polar substituent ispresent in at least about 0.03% by weight of the substituted celluloseacetate. In some embodiments, the nonmetal of the polar substituent ispresent in no more than about 75% by weight of the substituted celluloseacetate. The exact range of polar substituent weight percentage willdepend on, among other things, the chemical makeup of the polarsubstituent.

In one or more embodiments, the substituted cellulose acetate may haveproperties that may be imparted or enhanced by increasing or decreasingthe concentration of polar substituents or nonmetal atoms. In someembodiments, the substituted cellulose acetate may be water-soluble. Insome embodiments, the substituted cellulose acetate may bewater-swellable. In some embodiments, the substituted cellulose acetatemay be water resistant. In some embodiments, it may be desirable for thesubstituted cellulose acetate to have a relatively high sulfurpercentage and a relatively high degree of substitution for acetate. Inparticular, water-swellable materials are often marked by their abilityto absorb water and are used as water-stopping material, water-retainingmaterial, material supplies, and the like. In some embodiments, thesubstituted cellulose acetate may be degradable. In some embodiments,the substituted cellulose acetate may be biodegradable.

The substituted cellulose acetate of the present invention may beutilized as an absorbent material for a number of consumer applications.The present invention provides, in some embodiments, diapers comprisingan absorbent core comprising the substituted cellulose acetate of thepresent invention and an outer layer. Optionally, the diaper may furthercomprise a distribution layer designed to transfer wetness to theabsorbent core and/or an outer shell that covers at least a portion ofthe absorbent core.

In some embodiments, the distribution layer is interposed between theabsorbent core and the outer layer. In some embodiments the distributionlayer may be waterproof.

In some embodiments, the outer layer surrounds the absorbent core. Insome embodiments, the outer layer is waterproof. In some embodiments,the outer layer is configured to receive an insertion of the absorbentcore. The outer layer may also be colored or feature ornamental designsthat increases the visual attractiveness of the diaper. In someembodiments, the outer layer is configured with an opening to receive aninsertion of an absorbent core. In some embodiments, the outer layer maybe reusable.

In some embodiments, the outer layer is made from a material comprisinga material selected from the group consisting of polyethylene, nonwovenfilm, composite film, cloth, and combinations thereof.

In some embodiments, the diaper may be disposable. In some embodiments,at least a portion of the diaper may be reusable.

The present invention provides, in some embodiments, bandages comprisingan absorbent layer comprising a substituted cellulose acetate of thepresent invention and a strip designed to maintain the absorbent layerin contact with a wound. Optionally, the absorbent layer furthercomprises an active ingredient selected from the group consisting ofantibiotics, analgesics, antipyretics, antimicrobials, antiseptics,antiallergies, anti-acne, anesthetics, anti-inflammatories, hemostats,cosmetics, vitamins, vasodilators, emollients, pH regulators,antipruritics, counterirritants, antihistamines, steroids, andcombinations thereof.

In some embodiments, the antiseptic may comprise at least one transitionmetal. Suitable examples of a transition metal include, but are notlimited to, aluminum, nickel, copper, zinc, titanium, iron, and silver.

In some embodiments, the wound is an incision, a laceration, anabrasion, a puncture wound, a penetration wound, or any combinations ofthese.

In some embodiments, the strip may be elastic. In some embodiments, thestrip may be adhesive. In some embodiments, the strip comprises amaterial selected from the group consisting of: woven fabric, nonwovenfabric, plastic, latex, and combinations thereof.

In some embodiments, the cigarette filter materials of the presentinvention comprise a segmented filter or a section of a filtercomprising a substituted cellulose acetate of the present invention. Insome embodiments, the cigarette filter materials of the presentinvention further comprise a conventional secondary cellulose diacetate.Optionally, the cigarette filter materials further comprise aplasticizer. Without being limited by theory, it is believed that thesubstituted cellulose acetate should increase the degradability of thecigarette filter material.

Suitable examples of plasticizers for use with cigarette filter materialrelated embodiments include phthalate, acetyl triethyl citrate, triethylcitrate, acetyltributyl citrate, dibutylsebacate, triacetin, glyceryltriacetate, polyethylene glycol, propylene glycol, and glycerin.

In some embodiments, the substituted cellulose acetate may be a tow. Insome embodiments, the substituted cellulose acetate is formed in a rodshape.

In some embodiments, the smoking devices of the present inventioncomprise a smokeable substance and a cigarette filter that comprises asubstituted cellulose acetate filament of the present invention. As usedherein, a “smokeable substance” includes anything (e.g., tobacco) thatmay be burned and its smoke can be tasted or inhaled. Tobaccos may beutilized in any number of different forms including, but not limited to,dried, fermented, cured, cut, and the like.

In some embodiments, a smoking device may comprise a cigar, a pipe, acigarette, a vaporizer, and the like.

In some embodiments, the coated seeds of the present invention comprisea seed that is coated with a coating that comprises a substitutedcellulose acetate of the present invention. Optionally, the coated seedsfurther comprise a secondary growth augmentation coating. Suitableexamples of secondary growth augmentation coating may be selected fromthe group consisting of primary nutrients, secondary nutrients,hormones, insecticides, pesticides, herbicides, fungicides,bactericides, pigments, binders, surfactants, glidants, and combinationsthereof.

Suitable examples of primary nutrients for use in conjunction with someembodiments of the present invention may include, but are not limitedto, ammonium nitrate, urea, ammonium phosphate, ammonium sulfate, ureaphosphate, ammonium molybdate, potassium nitrate, potassium phosphate,potassium hydroxide, potassium sulfate, and potassium chloride.

Suitable examples of secondary nutrients are selected from the groupconsisting of magnesium sulfate, calcium nitrate, sodium borate,magnesium nitrate, chelated complex of copper, calcium, iron, zinc,magnesium, manganese, ammonium molybdate, sodium molybdate, benzoicacid, and salicylic acid.

Suitable examples of binders for use in conjunction with someembodiments of the present invention may include, but are not limitedto, methylcellulose, carboxymethylcellulose, hydroxymethylcellulose,hydroxypropylcellulose, polyvinyl alcohol, polyvinyl acetate, povidone,copolyvidone, derivatives thereof, and combinations thereof.

Suitable examples of surfactants for use in conjunction with someembodiments of the present invention may include, but are not limitedto, lecithin, sodium lauryl sulfate, polysorbate 60, polysorbate 80,polyoxethylene polyoxypropylene block copolymer, derivates thereof, andcombinations thereof.

Suitable examples of pigments for use in conjunction with someembodiments of the present invention may include, but are not limitedto, titanium dioxide, iron oxide, natural pigments, natural dyes, FD&Ccolorants, D&C lakes, derivatives thereof, and combinations thereof.

Suitable examples of glidants for use in conjunction with someembodiments of the present invention may include, but are not limitedto, talc, colloidal silicon dioxide, stearic acid, derivatives thereof,and combinations thereof.

Suitable examples of herbicides for use in conjunction with someembodiments of the present invention may include, but are not limitedto, glyphosate, dicamba, alanchlor, meolachlor, oxabetrinil,thiocarbamate 5-ethyl-N,N-dipropyl-thiocarbamate, acetochlor,derivatives thereof, and combinations thereof.

Suitable examples of antidotal compounds for use in conjunction withsome embodiments of the present invention may include, but are notlimited to, fluorazole, cyometrinil, N,N-diallyl dichloroacetamide,derivatives thereof, and combinations thereof.

Suitable examples of fungicide, bactericide, insecticide, and pesticidefor use in conjunction with some embodiments of the present inventionmay include, but are not limited to, inorganic coppers, organic coppers,heavy metal compounds, propenoic acids, oximine ethers, substitutedoximine ethers, derivatives thereof, and combinations thereof.

Suitable examples of plant hormones for use in conjunction with someembodiments of the present invention may include, but are not limitedto, auxins, gibberellic acids, cytokines, derivatives thereof, andcombinations thereof.

In some embodiments, the coated pharmaceutical compositions of thepresent invention comprise a pharmaceutical composition that is coatedwith a coating that comprises a substituted cellulose acetate of thepresent invention.

In some embodiments, the pharmaceutical composition for use inconjunction with some embodiments of the present invention may include,but are not limited to, analgesics, anti-inflammatory agents,anti-arrhythmic agents, anti-asthma agents, anti-bacterial agents,anti-viral agents, anti-coagulants, anti-dementia agents,anti-depressants, anti-diabetics, anti-hypertensive agents,anti-malarials, anti-migraine agents, anti-muscarinic agents,anti-neoplastic agents, immunosuppressants, anti-protozoal agents,anti-thyroid agents, anti-tussives, anxiolytics, sedatives, hypnotics,neuroleptics, neuro-protective agents, beta blockers, cardiac inotropicagents, cell adhesion inhibitors, corticosteroids, cytokine receptoractivity modulators, diuretics, anti-parkinsonian agents,gastrointestinal agents, histamine H-receptor antagonists, keratolytics,lipid regulating agents, muscle relaxants, nitrates, anti-fungal agents,anti-anginal agents, non-steroid anti-asthma agents, nutritional agents,sex hormones, stimulants, anti-erectile dysfunction agents, anesthetics,antihistamines, decongestants, cough suppressants, demulcents,expectorants, derivatives thereof, combinations thereof, and mixturesthereof.

In some embodiments, the pharmaceutical composition for use inconjunction with some embodiments of the present invention may include,but are not limited to, pseudoephedrine, phenylpropanolamine,phenylephrine, ephedrine, dextromethorphan, chlorphedianol,carbetapentane, caramiphen, noscapine, diphenhydramine, codeine,menthol, hydrocodone, hydromorphone, fominoben, glyceryl guaiacolate,terpin hydrate, ammonium chloride, N-acetylcysteine, bromhexine,ambroxol, chlorpheniramine, brompheniramine, dexchlorpheniramine,dexbrompheniramine, tripolidine, azatadine, doxylamine, tripelennamine,cyproheptadine, hydroxyzine, elemastine, carbinoxamine, phenindamine,bromodiphenhydramine, pyilamine, acrivastine, AHR-11325, astemizole,azelastine, cetirizine, ebastine, ketotifen, lodoxamide, loratidine,levocabastine, mequitazine, oxatomide, setastine, tazifylline,temelastine, terfenadine, terbutaline, atropine, aminophylline,epinephrine, isoprenaline, metaproterenol, bitoterol, theophylline,albuterol, aspirin, acetaminophen, ibuprofen, naproxen, phenol,benzocaine, hexyl resorcinol, dyclonine, derivatives thereof,combinations thereof, the pharmaceutically acceptable salts thereof, andmixtures thereof.

The present invention provides kits for detection of an analytecomprising a reporter molecule that is coated with a coating thatcomprises a substituted cellulose acetate of the present invention.

The reporter molecule for use in conjunction with some embodiments ofthe present invention may include, but are not limited to, an antibody,a protein, an enzyme, a peptide, a nucleic acid, a small molecule, afluorophore, derivatives thereof, and combinations thereof.

In some embodiments, the coating is water-soluble or water-swellable. Ingeneral, the coating provides a protective layer that can delay orprevent the degradation (e.g., denaturation, cleavage) of the reportermolecule during storage.

In some embodiments, the coated stents of the present invention comprisea stent having an outer coating layer that comprises a substitutedcellulose acetate of the present invention and an inner coating layerthat comprises a pharmaceutical composition.

In some embodiments, the stent comprises a shape-memory material.Suitable examples of shape-memory material for use in conjunction withsome embodiments of the present invention may include, but are notlimited to, zinc alloys, copper alloys, gold alloys, iron alloys,copper-zinc-aluminum-nickel alloys, copper-aluminum-nickel alloys, andnickel-titanium alloys.

In some embodiments, the stent comprises a polymer. Suitable examples ofpolymer for use in conjunction with some embodiments of the presentinvention may include, but are not limited to, fibrin, polylactic acid,silicones, polyurethanes, polyesters, vinyl homopolymers, vinylcopolymers, acrylate homopolymers, acrylate copolymers, polyethers,cellulosics, derivatives thereof, and combinations thereof.

In some embodiments, the pharmaceutical composition is selected from thegroup consisting of: glucocorticoids, heparin, hirudin, tocopherol,angiopeptin, aspirin, growth factors, oligonucleotides, anti-plateletagents, anti-coagulant agents, anti-mitotic agents, anti-oxidants,anti-metabolite agents, anti-inflammatory agents, and combinationsthereof.

In some embodiments, the potting soil compositions of the presentinvention comprise an organic compost and an absorbent compositioncomprising a substituted cellulose acetate of the present invention.Optionally, the potting soil composition may further comprise at leastone component selected from the group consisting of loam, diatomaceousearth component, Perlite component, and combinations thereof.

In some embodiments, loam comprises components selected from the groupconsisting of sand, silt, clay, and combinations thereof.

In some embodiments, the diatomaceous earth component comprises at leastone component selected from the group consisting of diatomaceous earth,phosphate, magnesium, potassium, nitrogen, and combinations thereof.

In some embodiments, the amended soil compositions of the presentinvention comprise a soil composition and a water retention additivecomprising a substituted cellulose acetate of the present invention.Optionally, the amended soil composition may further comprise anadditive selected from the group consisting of sand, silt, clay,calcined clay, iron oxide, dry resin, and combinations of these.

Suitable dry resins for use in conjunction with some embodiments of thepresent invention may include, but are not limited to, acrylic polymer,polyvinyl acetate polymer, vinyl acetate copolymer, derivatives thereof,and combinations thereof.

In some embodiments, the drilling fluids of the present inventioncomprise a base fluid and a viscosifier comprising a substitutedcellulose acetate of the present invention. Optionally, the drillingfluid may further comprise an additive selected from the groupconsisting of fluid loss control agents, clay inhibitors, lubricants,weighting agents, viscosifiers, and any combinations thereof.

In some embodiments, the base fluid may be an aqueous fluid, anoil-based fluid, a synthetic fluid, or an emulsion.

In some embodiments, the present invention provides articles comprisinga nonwoven layer that comprises fibers from a substituted celluloseacetate of the present invention.

In some embodiments, the nonwoven layer may include, but are not limitedto, diapers, feminine hygiene products, wet wipes, bandages, disposabletowels, disposable slippers, isolation gowns, surgical gowns, surgicaldrapes and covers, surgical scrub suits, caps, filters (e.g., HEPAfilters; water, coffee, tea bags; liquid cartridges, vacuum bags;geotextiles (e.g., geomembranes); carpet backing; and envelopes.

In some embodiments, the present invention provides a process for makinga substituted cellulose acetate tow comprising spinning a dopecomprising a solution of cellulose diacetate and substituted celluloseacetate of the present invention; and solvent; taking-up the as-spunsubstituted cellulose acetate filaments; forming a tow from thesubstituted cellulose acetate filaments; crimping the tow; conditioningthe crimped tow; and baling the dried crimped tow. Optionally, theprocess may further comprise the step of lubricating the substitutedcellulose acetate filaments.

In some embodiments, the solvent is water, acetone, methylethyl ketone,methylene chloride, dioxane, dimethyl formamide, methanol, ethanol,glacial acetic acid, supercritical CO₂, any suitable solvent capable ofdissolving the aforementioned polymers, or any combination thereof. Byway of nonlimiting example, a solvent for cellulose acetate may be anacetone/methanol mixture.

In some embodiments, the substituted cellulose acetate is spun in aspinneret. In some embodiments, the spinneret comprises holes. Theseholes may be of any shape that is compatible with one or moreembodiments of the present invention. The spinneret design and/orspinning parameters may affect the rate at which the solvent evaporatesfrom the filament, which may affect the size, cross-sectional shape,strength, and processability of the filaments. In some embodiments, aspinneret may comprise a plurality of holes spaced at least 0.070 inchesapart. In some embodiments, spinnerets for use in conjunction with thepresent invention may comprise a plurality of extrusion holes in a donutconfiguration. As used herein, “donut configuration” refers to any shape(circular, ovular, polygonal, triangular, and the like) having a void inthe middle, wherein the void does not have holes for extrusion. As usedherein, the terms “holes” and “extrusion holes,” when used inconjunction with a spinnerets design, may be used interchangeablyreferring generally to openings through which the dope is extruded. Insome embodiments, extrusion holes may be tapered, e.g., countersinks,with capillary exits. Tapering may be at a constant angle or at morethan one angle. In some embodiments, extrusion holes within a singlespinneret may have different tapering angles. In some embodiments, theextrusion holes and/or capillary exits may have a cross-sectional shapethat produces a desired filament cross-sectional shape. Examples ofextrusion hole and/or capillary exit cross-sectional shapes may include,but not be limited to, circular, substantially circular, ovular,substantially ovular, crescent, multi-lobal, polygonal (e.g., liketripods, tetrapods, stars, triangles, squares, trapezoids, pentagons,hexagons, and so on with sides of even lengths or varying lengths),polygonal with rounded corners, and any hybrid thereof. In someembodiments, a spinneret may comprise at least two differentcross-sectional shaped extrusion holes and/or capillary exits. In someembodiments, a spinneret may comprise at least two different sizeextrusion holes and/or capillary exits. In some embodiments, the sizeand/or cross-sectional shape of an extrusion hole may vary from that ofthe corresponding capillary exit.

In some embodiments, the spinning parameters may include extrudingfilaments at a drawdown ratio (fiber exit speed to take-up speed)ranging from about 0.7 to about 1.6.

It should be understood by one skilled in the art that extruding doesnot imply a single method or action for producing the filaments andcould be interchanged with, at least, spinning, expelling, and the like.

In some embodiments, the methods of the present invention compriseproviding substituted cellulose acetate of the present invention andplacing the substituted cellulose acetate in an absorbent article. Insome embodiments, the absorbent article may be any article (e.g., agarment, a gel, a piece of furniture, etc.) that may utilize anabsorbent material. Suitable examples of absorbent articles may include,but are not limited to, diapers, incontinence garments, bandages,surgical pads, hot and cold therapy packs, water beds, artificial snow,and combinations thereof. In some embodiments, the absorbent article isdisposable and/or degradable.

In some embodiments, the substituted cellulose acetate may be placed inthe inner portion of an absorbent article. In some embodiments, thesubstituted cellulose acetate may be placed on the outer portion of anabsorbent article. In some embodiments, the substituted celluloseacetate may be part of the outer portion of an absorbent article. Theterm “placing” is not intended to limit the present invention to anyspecific mode of action.

In some embodiments, the methods of the present invention comprisecoating a seed with a coating comprising a substituted cellulose acetateof the present invention. Optionally, the coating may further compriseat least one ingredient selected from the group consisting of aplasticizer, a binder, a wax, a stabilizer, and a colorant.

In some embodiments, methods of the present invention comprise coating apharmaceutical composition with a coating comprising a substitutedcellulose acetate of the present invention. Optionally, the coating mayfurther comprise an additive selected from the group consisting of aplasticizer, an annealing agent, an emulsifying agent, an emulsionstabilizer, and combinations of these.

In some embodiments, the annealing agent comprises a water-solublepolymer selected from the group consisting of hydroxypropyl cellulose,hydroxypropyl methyl cellulose, methyl cellulose, methyl ethylcellulose, polyvinylpyrrolidone, sodium carboxymethylcellulose,derivatives thereof, and combinations thereof.

In some embodiments, the methods of the present invention compriseproviding an adhesive comprising a substituted cellulose acetate of thepresent invention and applying the adhesive on a surface. In someembodiments, the surface may be selected from the group consisting ofwood, plastic, paper, glass, cardboard, and combinations of these. Insome embodiments, the adhesive is a dispersion. Optionally, the adhesivemay further comprise a solvent and/or an additive.

In some embodiments, the solvent may be aqueous. In some embodiments,the solvent may be a mixture such as an organic/water solvent. In someembodiments, the solvent may be present in about 40% to about 99% byweight of the adhesive.

In some embodiments, the additive comprises an additive selected fromthe group consisting of multi-valent salts (e.g., zirconium salts suchas zirconium carbonate), polyamide epichlorohydrin resins, aldehydes(e.g., glyoxal, gluteraldehyde, hydroxyadipaldehyde), formaldehydecrosslinkers (e.g., zero-formaldehyde, low-formaldehyde crosslinkers),polyvinyl acetates, polyvinyl alcohols, polystyrenes, polylactic acids,derivatives thereof, and combinations thereof.

In some embodiments, the present invention provides a paint compositioncomprising a pigment and a stabilizing film forming agent that comprisesa substituted cellulose acetate of the present invention and coating asurface with the paint. Optionally, the paint may further comprise atleast one element selected from the group consisting of: a solvent, afiller, an antifreeze additive, a catalyst, a thickener, an adhesionpromoter, a UV stabilizer, a de-glossing agent, a biocide, andcombinations thereof.

Suitable examples of solvents include, but are not limited to, analiphatic solvent, an aromatic solvent, an alcohol, a ketone, ahydrocarbon, an ester, a petroleum distillate, water, derivativesthereof, and combinations thereof.

Suitable examples of pigments include pigments selected from the groupconsisting of clay, calcium carbonate, mica, silica, talc, titaniumdioxide, derivatives thereof, and combinations thereof.

Suitable examples of filters include fillers selected from the groupconsisting of: diatomaceous earth, talc, lime, barite, clay, derivativesthereof, and combinations of these.

In some embodiments, the present invention provides a method ofproviding a paint comprising a pigment; and a stabilizing film formingagent that comprises a substituted cellulose acetate comprising a polarsubstituent that comprises an oxygen atom covalently bonded to anonmetal selected from the group consisting of: sulfur, phosphorus,boron, and chlorine; wherein the nonmetal is present in at least about0.01% by weight of the substituted cellulose acetate; and coating asurface with the paint.

The methods of the present invention comprise providing a stabilizingfilm forming agent comprising a substituted cellulose acetate of thepresent invention and adding the stabilizing film forming agent to anemulsion. Suitable examples of emulsion include, but are not limited to,cosmetic product, hair styling product, photographic film, cuttingfluid, skin ointment, paste, balm, oil, wax, detergent, beverage, andcombinations of these.

The methods of the present invention comprise providing a thickeningagent comprising a substituted cellulose acetate of the presentinvention and adding the thickening agent to a food composition.Suitable food compositions may include, but are not limited to, soups,gravy, desserts, jellies, candies, and the like.

To facilitate a better understanding of the present invention, thefollowing examples of preferred embodiments are given. In no way shouldthe following examples be read to limit, or to define, the scope of theinvention.

Example 1

Some adhesive compositions comprising substituted cellulose acetate ofthe present invention were tested for their adhesive properties onvarious substrates including wood and cardboard using a lap shear test.These results were compared with commercially available glue (e.g.,ELMER'S GLUE ALL®). A summary of the results is shown below in Tables 1Aand 1B.

TABLE 1A Lap Shear Test Results Adhesive Solvent Solids FormulationBreak Description System Drying (wt %) Used (g) (KGF) Poly(vinylacetate)- emulsion ambient 1 hr 54 0.0503 58.94 based adhesive (ELMER'SGLUE ALL ®) Cellulose Acetate aqueous ambient 1 hr 10 0.0512 43.86Adhesive 1 Cellulose Acetate aqueous ambient 20 0.0515 >107 Adhesive 22.25 hr Cellulose Acetate aqueous ambient 15 0.0506 >107 Adhesive 3 2.25hr Cellulose Acetate mixed ambient 10 0.0506 >107 Adhesive 4 organic/2.5 hr aqueous Cellulose Acetate aqueous ambient 15 0.0498 >107 Adhesive2 2.5 hr Poly(vinyl acetate)- ambient 27 0.05 >107 based adhesiveovernight (ELMER'S SCHOOL GLUE) Cellulose Acetate aqueous 1 hr oven 100.0505 >107 Adhesive 5 (120° C.) Cellulose Acetate aqueous 1 hr oven 100.0505 >107 Adhesive 5 (120° C.) Cellulose Acetate aqueous 1 hr oven 100.0518 >107 Adhesive 5 (120° C.)

TABLE 1B Lap Shear Test Results Special Sulfur Description NewtonsSubstrate Treatment (mg/kg) Results Poly(vinyl 578.003951 cardboardpaper acetate)-based failure adhesive (ELMER'S GLUE ALL ®) Cellulose430.119669 cardboard not paper Acetate measured failure Adhesive 1Cellulose >1000 wood 4940 exceeded Acetate load cell Adhesive 2 capacityCellulose >1000 wood 4530 exceeded Acetate load cell Adhesive 3 capacityCellulose >1000 wood 4940 exceeded Acetate load cell Adhesive 4 capacityCellulose >1000 wood 4940 exceeded Acetate load cell Adhesive 2 capacityPoly(vinyl >1000 wood exceeded acetate)-based load cell adhesivecapacity (ELMER'S SCHOOL GLUE) Cellulose >1000 wood 5570 exceededAcetate load cell Adhesive 5 capacity Cellulose >1000 wood 1 hr in 5570exceeded Acetate refrigerator load cell Adhesive 5 (4° C.) capacityCellulose >1000 wood 1 hr in 5570 exceeded Acetate refrigerator loadcell Adhesive 5 (4° C.) capacity

Substituted cellulose acetates with high sulfur content in accordancewith one or more embodiments of the present invention (batches CelluloseAcetate Adhesive 1-5) were prepared and tested as a wood adhesive usingINSTRON® (Model 3366) Lap Shear test. The results, including the amountof sulfur in the solution (mg of sulfur per kg of sulfur), aresummarized in Tables 1A and 1B above. Two small wooden blocks were gluedtogether using a 10% aqueous solution of the adhesives and allowed todry. The resulting blocks were difficult to separate (i.e., none of theblocks broke in the tensile testing setup used). When enough force wasapplied to separate the blocks, the wood fibers broke which suggeststhat the substituted cellulose acetate adhesive is as strong as the woodfibers. Substituted cellulose acetate adhesives were also used to gluecardboard. The cardboard was also difficult to separate. Substitutedcellulose acetate adhesives were optically clear and have a high glosswhich may be desirable in commercial applications. Substituted celluloseacetate adhesives dried in less than 30 minutes at ambient conditions.

This Example shows, among many things, that substituted celluloseacetate with high sulfur content is effective as an adhesive on avariety of substrates.

Example 2

This Example describes the synthesis of a sulfate substituted celluloseacetate of the present invention. In the first step, cellulose wasacetylated in the presence of acetic anhydride and sulfuric acid. Thepreparation of cellulose, acetic acid, acetic anhydride and sulfuricacid is similar to the preparation involved in a standard secondarycellulose acetate diacetate production. Next, the reagents were combinedto initiate the acetylation reaction. This reaction was allowed to reachcompletion and then reacted with any excess anhydride by the addition ofwater. The reaction rate and temperature may be closely monitored andvaried to control certain polymer properties.

Next, the acetylated cellulose (i.e., cellulose acetate) was hydrolyzedin the presence of acetic acid without precipitation and subsequentredissolving steps. This reduced the cellulose acetate to the targetacetate DS levels by carefully controlling the reaction temperature andtime. Water was added as needed to maintain polymer solubility. Thisproduced a sulfate substituted cellulose acetate product havingunexpected and surprisingly high sulfur content.

Finally, the solid was precipitated from the solvent system usingappropriate dilutant. The product was washed as needed to remove excesssolvent and dried to desired solids level.

Example 3

In this Example, a water-swellable cellulose acetate (low sulfurcontent) and substituted cellulose acetate (high sulfur content) weretested for their ability to absorb water using a thermogravimetricanalysis (TGA). Each sample was placed in a TGA system and subjected tothe following temperatures. The samples were ramped to 110° C. at 20°C./min. The temperature was held at 110° C. for 30 minutes. Thetemperature was then ramped to 650° C. at 20° C./min. The sample gas wasthen switched to air and the temperature was held at 650° C. for 30minutes. In each test run, the cellulose acetate samples were limited toless than 100 mg.

FIGS. 2-5 show the various TGA analysis runs measuring the waterabsorbency of high sulfate substituted cellulose acetate and low sulfatesubstituted cellulose acetate.

FIG. 2 shows a TGA analysis of water-saturated, water-swellablecellulose acetate (WSCA) 1036 RT-16 dry sample. WSCA 1036 RT-16 is ahigh sulfate substituted cellulose acetate particulate sample containingapproximately 0.5% of sulfur by weight of the cellulose acetate. Astemperature is ramped up and held at 110° C., the total weight of thewater-saturated sample decreases as the water dried off. The temperatureof the TGA system was then ramped to and held at 650° C., thus allowingthe high sulfate substituted cellulose acetate to decompose. WSCA 1036RT-16 was able to absorb approximately 1440% water by weight as the drysample or over 14 times its weight in water.

FIG. 3 shows TGA duplicate runs for two WSCA 1037 RT-16 dry samples.Compared to the WSCA 1036 RT-16, the WSCA 1037 RT-16 is a low sulfursubstituted cellulose acetate (the DS of acetates are similar). Thedetected water absorption for the two samples were 76.91% and 81.31%,which corresponds to water to dry WSCA ratios of 3.35 and 4.37respectively.

FIG. 4 shows TGA duplicate runs for two saline water (−0.9%) saturatedWSCA 1036 (high sulfate) RT-16 samples. The two samples contained 87.05%and 92.14% saline water which corresponded to water to dry WSCA ratiosof 7.48 and 13.6 respectively.

FIG. 5 shows TGA duplicate runs for saline water (−0.9%) saturated WSCA1037 RT-16 sample. The two samples contained 78.31% and 83.91% salinewater which corresponded to water to dry WSCA ratios of 3.72 and 5.46.

This Example shows, among many things, that a substituted celluloseacetate having a high sulfur content is able to absorb water (bothdeionized and saline) several times its weight. When compared withsubstituted cellulose acetate with low sulfur content, the high sulfursubstituted cellulose acetate displayed superior water (both DI andsaline) absorption.

Example 4

Various additives were added to some adhesive compositions comprisingsubstituted cellulose acetate of the present invention. The resultingcompositions were tested for their adhesive properties on woodsubstrates (¼″ pine strips 1.5″ in width) using INSTRON® (Model 3366)Lap Shear test. Summaries of the results are shown below in Tables 2 and3.

TABLE 2 Cellulose Acetate Adhesive 6 (620 mg/kg Sulfur) Zr as % of totalsolution (% of Average Break Average Standard solids) (Kgf)* Break(psi**) Deviation      0 (0) 179 263 32 0.04% (0.2%) 271 398 110 0.08%(0.4%) 280 411 35 0.16% (0.9%) 300 441 71 0.32% (1.8%) 362 532 45*average of 6 replicates **lap shear of 1.5″ × 1″ adhered area

TABLE 3 Cellulose Acetate Adhesives 7-8 Additive CA adhesive 7 CAadhesive 8 No Additive (Kgf at bond break) 225 349 Ammonium Zirconium348 245 Carbonate (Kgf at bond break) Polyvinyl Acetate MW 140000 271210 (Kgf at bond break) Polyvinyl Alcohol MW~150000 not tested 154 (Kgfat bond break) Sulfur Levels 520 mg/kg 557 mg/kg

As shown in Tables 2, the addition of zirconium can increase thestrength required to break the bond formed by the cellose acetateadhesive compositions (substituted cellulose acetate with high sulfurcontent). Table 3 shows results of lap shear testing of celluloseacetate adhesives 7 and 8 with ammonium zirconium carbonate (0.08% Zr),MW 140,000 polyvinyl acetate (14% of solid) and MW 150,000 polyvinylalcohol (14% of solid). The sulfur content of cellulose acetateadhesives 6, 7, and 8 are 620 mg/kg, 520 mg/kg, and 557 mg/kgrespectively.

Therefore, the present invention is well adapted to attain the ends andadvantages mentioned as well as those that are inherent therein. Theparticular embodiments disclosed above are illustrative only, as thepresent invention may be modified and practiced in different butequivalent manners apparent to those skilled in the art having thebenefit of the teachings herein. Furthermore, no limitations areintended to the details of construction or design herein shown, otherthan as described in the claims below. It is therefore evident that theparticular illustrative embodiments disclosed above may be altered,combined, or modified and all such variations are considered within thescope and spirit of the present invention. The invention illustrativelydisclosed herein suitably may be practiced in the absence of any elementthat is not specifically disclosed herein and/or any optional elementdisclosed herein. While compositions and methods are described in termsof “comprising,” “containing,” or “including” various components orsteps, the compositions and methods can also “consist essentially of” or“consist of” the various components and steps. All numbers and rangesdisclosed above may vary by some amount. Whenever a numerical range witha lower limit and an upper limit is disclosed, any number and anyincluded range falling within the range is specifically disclosed. Inparticular, every range of values (of the form, “from about a to aboutb,” or, equivalently, “from approximately a to b,” or, equivalently,“from approximately a-b”) disclosed herein is to be understood to setforth every number and range encompassed within the broader range ofvalues. Also, the terms in the claims have their plain, ordinary meaningunless otherwise explicitly and clearly defined by the patentee.Moreover, the indefinite articles “a” or “an,” as used in the claims,are defined herein to mean one or more than one of the element that itintroduces. If there is any conflict in the usages of a word or term inthis specification and one or more patent or other documents that may beincorporated herein by reference, the definitions that are consistentwith this specification should be adopted.

What is claimed:
 1. A coated seed comprising: a seed having a coatingthat comprises a substituted cellulose acetate comprising a polarsubstituent that comprises an oxygen atom covalently bonded to anonmetal selected from the group consisting of: sulfur, phosphorus,boron, and chlorine; wherein the nonmetal is present in at least about0.01% by weight of the substituted cellulose acetate.
 2. The coated seedof claim 1 wherein the nonmetal is present in no more than about 25% byweight of the substituted cellulose acetate.
 3. The coated seed of claim1 wherein the seed further comprises a secondary growth augmentationcoating.
 4. The coated seed of claim 3 wherein the secondary growthaugmentation coating comprises an element selected from the groupconsisting of: a primary nutrient, a secondary nutrient, a hormone, aninsecticide, a herbicide, a fungicide, a bactericide, a pigment, abinder, a surfactant, a glidant, and any combination thereof.
 5. Acoated pharmaceutical composition comprising: a pharmaceuticalcomposition having a coating that comprises a substituted celluloseacetate comprising a polar substituent that comprises an oxygen atomcovalently bonded to a nonmetal selected from the group consisting of:sulfur, phosphorus, boron, and chlorine; wherein the nonmetal is presentin at least about 0.01% by weight of the substituted cellulose acetate.6. The coated pharmaceutical composition of claim 5 wherein the nonmetalis present in no more than about 25% by weight of the substitutedcellulose acetate.
 7. The coated pharmaceutical composition of claim 5wherein the pharmaceutical composition comprises a pharmaceuticalcomposition selected from the group consisting of: an analgesic, ananti-inflammatory agent, an anti-arrhythmic agent, an anti-asthma agent,an anti-bacterial agent, an anti-viral agent, an anti-coagulant, ananti-dementia agent, an anti-depressant, an anti-diabetic, ananti-hypertensive agent, an anti-malarial, an anti-migraine agent, ananti-muscarinic agent, an anti-neoplastic agent, an immunosuppressant,an anti-protozoal agent, an anti-thyroid agent, an anti-tussive, ananxiolytic, a sedative, a hypnotic, a neuroleptic, a neuro-protectiveagent, a beta blocker, a cardiac inotropic agent, a cell adhesioninhibitor, a corticosteroid, a cytokine receptor activity modulator, adiuretic, an anti-parkinsonian agent, a gastrointestinal agent, ahistamine H-receptor antagonist, a keratolytic, a lipid regulatingagent, a muscle relaxant, a nitrate, an anti-fungal agent, ananti-anginal agent, a non-steroid anti-asthma agent, a nutritionalagent, a sex hormone, a stimulant, an anti-erectile dysfunction agent,an anesthetic, an antihistamine, a decongestant, a cough suppressant, ademulcent, an expectorant, and any combination thereof.
 8. The coatedpharmaceutical composition of claim 5 wherein the pharmaceuticalcomposition comprises a pharmaceutical composition selected from thegroup consisting of: pseudoephedrine, phenylpropanolamine,phenylephrine, ephedrine, dextromethorphan, chlorphedianol,carbetapentane, caramiphen, noscapine, diphenhydramine, codeine,menthol, hydrocodone, hydromorphone, fominoben, glyceryl guaiacolate,terpin hydrate, ammonium chloride, N-acetylcysteine, bromhexine,ambroxol, chlorpheniramine, brompheniramine, dexchlorpheniramine,dexbrompheniramine, tripolidine, azatadine, doxylamine, tripelennamine,cyproheptadine, hydroxyzine, elemastine, carbinoxamine, phenindamine,bromodiphenhydramine, pyilamine, acrivastine, AHR-11325, astemizole,azelastine, cetirizine, ebastine, ketotifen, lodoxamide, loratidine,levocabastine, mequitazine, oxatomide, setastine, tazifylline,temelastine, terfenadine, terbutaline, atropine, aminophylline,epinephrine, isoprenaline, metaproterenol, bitoterol, theophylline,albuterol, aspirin, acetaminophen, ibuprofen, naproxen, phenol,benzocaine, hexyl resorcinol, dyclonine, pharmaceutically acceptablesalt thereof, and any combination thereof.
 9. A kit for detection of ananalyte comprising: a reporter molecule having a coating that comprisesa substituted cellulose acetate comprising a polar substituent thatcomprises an oxygen atom covalently bonded to a nonmetal selected fromthe group consisting of: sulfur, phosphorus, boron, and chlorine;wherein the nonmetal is present in at least about 0.01% by weight of thesubstituted cellulose acetate.
 10. The kit of claim 9 wherein thenonmetal is present in no more than about 25% by weight of thesubstituted cellulose acetate.
 11. The kit of claim 9 wherein thereporter molecule comprises a reporter molecule selected from the groupconsisting of: an antibody, a protein, an enzyme, a peptide, a nucleicacid, a small molecule, a fluorophore, a derivative thereof, and anycombination thereof.
 12. The kit of claim 9 wherein the coating iswater-soluble, water-swellable, or water resistant.
 13. A coated stentcomprising: a stent having an outer coating layer that comprises asubstituted cellulose acetate comprising a polar substituent thatcomprises an oxygen atom covalently bonded to a nonmetal selected fromthe group consisting of: sulfur, phosphorus, boron, and chlorine;wherein the nonmetal is present in at least about 0.01% by weight of thesubstituted cellulose acetate; and an inner coating layer that comprisesa pharmaceutical composition.
 14. The coated stent of claim 13 whereinthe nonmetal is present in no more than about 25% by weight of thesubstituted cellulose acetate.
 15. The coated stent of claim 13 whereinthe stent comprises a shape-memory material.
 16. The coated stent ofclaim 13 wherein the stent comprises a material selected from the groupconsisting of: a zinc alloy, a copper alloy, a gold alloy, an ironalloy, a copper-zinc-aluminum-nickel alloy, a copper-aluminum-nickelalloy, a nickel-titanium alloy, a polymer, and any combination thereof.17. The coated stent of claim 16 wherein the polymer comprises a polymerselected from the group consisting of: a fibrin, a polylactic acid, asilicone, a polyurethane, a polyester, a vinyl homopolymer, a vinylcopolymer, an acrylate homopolymer, an acrylate copolymer, a polyether,a cellulosic, and any combination thereof.
 18. The coated stent of claim13 wherein the pharmaceutical composition comprises a pharmaceuticalcomposition selected from the group consisting of: a glucocorticoid, aheparin, a hirudin, a tocopherol, an angiopeptin, an aspirin, a growthfactor, an oligonucleotide, an anti-platelet agent, an anti-coagulantagent, an anti-mitotic agent, an anti-oxidant, an anti-metabolite agent,an anti-inflammatory agent, and any combination thereof.
 19. A methodcomprising: coating a seed with a coating comprising a substitutedcellulose acetate comprising a polar substituent that comprises anoxygen atom covalently bonded to a nonmetal selected from the groupconsisting of: sulfur, phosphorus, boron, and chlorine; wherein thenonmetal is present in at least about 0.01% by weight of the substitutedcellulose acetate.
 20. The method of claim 19 wherein the nonmetal ispresent in no more than about 25% by weight of the substituted celluloseacetate.
 21. The method of claim 19 wherein the degree of substitutionfor an acetate substituent is about 0.05 to about
 3. 22. The method ofclaim 19 wherein the coating further comprises at least one ingredientselected from the group consisting of: a plasticizer, a binder, a wax, astabilizer, a colorant, and any combination thereof.
 23. The method ofclaim 19 wherein the plasticizer comprises a plasticizer selected fromthe group consisting of: a glycerin, a glycerin ester, a polyethyleneglycol, a diethylene glycol, a propylene glycol, a dimethyl sulfoxide,any derivative thereof, and any combination thereof.
 24. A methodcomprising: coating a pharmaceutical composition with a coatingcomprising a substituted cellulose acetate comprising a polarsubstituent that comprises an oxygen atom covalently bonded to anonmetal selected from the group consisting of: sulfur, phosphorus,boron, and chlorine; wherein the nonmetal is present in at least about0.01% by weight of the substituted cellulose acetate.
 25. The method ofclaim 24 wherein the nonmetal is present in no more than about 25% byweight of the substituted cellulose acetate.
 26. The method of claim 24wherein the degree of substitution for an acetate substituent is about0.05 to about
 3. 27. The method of claim 24 wherein the coating furthercomprises an additive selected from the group consisting of: aplasticizer, an annealing agent, an emulsifying agent, an emulsionstabilizer, and any combination of these.
 28. The method of claim 24wherein the annealing agent comprises a water-soluble polymer selectedfrom the group consisting of: a hydroxypropyl cellulose, a hydroxypropylmethylcellulose, a methyl cellulose, a methyl ethyl cellulose, apolyvinylpyrrolidone, a sodium carboxymethylcellulose, and anycombination thereof.
 29. The method of claim 24 wherein the plasticizercomprises a plasticizer selected from the group consisting of: propyleneglycol, glycerin, glycerin ester, glyceryl triacetate, polyethyleneglycol, any derivative thereof, and any combination of these.